Teenage Exorcists

2:00 PM EST, February 8, 2012

Meet the teenage exorcists.

For the past year, Tess Scherkenback, Savannah Scherkenback, and Brynne Larson, from Phoenix, Arizona, say they have been purging demons from the possessed. But it's nothing like anything you've seen in the movies.

"I would just say we are like your average girl. We love shopping, we do all kinds of girly stuff, we don't chase boys, we chase demons," said Savannah Scherkenback.

By day they are serious high school and college students, and in their free time, like most young women, they like to socialize and go to the mall.

But one day last month, they took a break from their studies and performed an exorcism on 51-year-old Matt Beauvais, a construction worker, who believes he's possessed by demons.

Before the exorcism, the teens are mentored by Bob Larson, a self-taught exorcist, who has conducted thousands of his own exorcisms.

"The thing that caught my attention were thoughts of murder, revenge and unforgiveness," said Larson when briefing the girls before the exorcism.

INSIDE EDITION correspondent Lisa Guererro asked the girls, "Do you guys get nervous before you do this? I know you are still training."

"We get a little nervous sometimes. You never know what to expect," Brynne Larson said.

Bob Larson starts things off by pushing a Bible in Beauvais' chest, causing loud screams. But in a few moments Larson puts the women in charge of the exorcism.

"Get up murder. I break the curse," said Brynne Larson.

Beauvais believes he suffers from demons that go back generations.

During the exorcism Bob Larson steps in and gives tips to the women. "Make him pronounce his doom and go."

Brynne Larson then attempts to cast out Beauvais' demons by sending them to a place she calls the pit. "Murder, you go now. Go to the pit!"

Guererro asked Beauvais, "What would you say to people who say, 'That's obviously fake?' Do you believe that you have demons inside you?"

"I had a ton. This is how you get clean, dig in, dig in, dig in until there's nothing left," Beauvais said.

Exorcism actually runs in the family for 17-year-old Brynne Larson. She's Bob Larson's daughter with his wife Laura.

"It was something that she really wanted to do. There was a natural interest in it. I love that it was something that she initiated. It was something that she believed and is committed to," said Laura Larson

"What do people say when they see you, because you are probably breaking all the stereotypes of what people think are exorcists?" Guerrero asked the young women.

"I think the biggest shock is when they walk in the room and they see braces, teenage girls, sequins," said Savannah Scherkenback.

Brynn adds, "This isn't just to get media, this is to help others and really make a difference."

Guererro asked Brynne's father Bob Larson, "Is this a healthy thing for your daughter to do at 17?"

Larson responds, "Would I prefer her to be sleeping around, on drugs, getting high or drunk? No. She is doing something to help people."